Tire fitting / gearing on YJ

Stolz Jeeper

New member
hey i have a couple questions regarding tire fitting and regearing my diffs. i have an 89 YJ with a 3 inch body lift, i am looking to get 33 inch tires as soon as i have the $ (soon hopefully) will i need to lift my jeep more to make them fit without them rubbing? and about my gears, i have a 4.2 IL6 5 spd, i am not sure what my current gearing is, i am pretty sure it is stock. does anyone know the stock gear ratio for my jeep is, and if yes would it be wise to swap in a lower gear for more torque?

eric
 

i'm running 33x12.5 on my stock driveline (4.2/5 spd) with a 4"lift - some rubbing on the tub in the back - you can forget about 5th gear unless youre running over 65 on flat or downhill.... stock gearing is around 3:25or so - if you can find a set of 4cyl axles they are 4:11 but hard to find with limited slip and i think the ujoints have to change.... you dont want to run more than 33's on the stock axles as they're not beefy enuff to handle larger meat than that (you'll end up breaking shafts...)... you can look some more but thats the net of what i've seen since i've been here on jeepz..... g'luck and let us know what you end up doin!!!
 
Most common gearing for the 4.2L 5spd YJ, every one I've seen, is 3.07 gears. I had an '88 with the same setup, solved my power problems by dropping in a 350 ;)

You need 4"-4.5" total lift to clear 33" tires on a YJ. You can get by with your current lift by installing TJ fender flares. Easy to do, requires trimming some sheetmetal, but allows for larger tires with less lift.
 
Axles from a 2.5L 5spd Yj are a great swap as they are 4.10 gears, or better yet get a 4.10 front YJ axle and use a Ford 8.8 with 4.10 in the rear from a '95+ Exploder. I did this in my MJ with an XJ front axle.
 

ok guys thanks for the input, really helps. know of any affordable 2" - 3" lift kits?
 
I would definitely re-gear the axles. If you will be doing much highway driving, 4.10's might not be a bad choice if you want to get halfway respectable fuel economy. If you want to put power over economy then consider 4.56 gears... especially if you plan to go bigger than 33's in the future.

So many suspensions to choose from... The Rusty's link above is probably going to be the best price you will find on a worthwhile kit. Also consider Rubicon Express' Standard Duty lift (4"):

http://www.jeepinoutfitters.com/scripts/prodList.asp?idCategory=65
 

First of all thank you both for the responses and the links!
i am very interested in the rusty's offroad 4" suspension lift. i have three questions about it: is rusty's a high quality suspension system? how smooth do the springs ride? does the kit include everything i need to do it?

would it be possible to take out my body lift (3"), cut the spacers in a chop saw and install them so that it would be only a 1" body lift and 4" suspension, i dont think i would want a 7" lift.
 
I ran the Rusty's 4" kit for a while and have no complaints, the springs rode and flexed pretty well. The springs are well built with a full military wrap around one end and 1/2 on the other, giving good support to the main leaf.

You can cut down your body lift to whatever length you need, and new bolts are easy to come by. Good choice on the 1" BL with a 4" spring.
 
i was thinking that since i drive my jeep everyday and offroad only 1/4 of the time IF that, maybe i dont want 33 inch tires? and the type of offroad is different compared to most of u guys out there, here in saskatchewan, there isnt much for hills and rocks and trails, just the occasional mud pit in a field or something on the lines of that, maybe an odd rock or 2. do u think my gas milage will be pretty bad with 33s? its just a thought but i would like to know about the milage before i jump the gun and make a mistake that i will regret.
 

I have 33" and just got done thowing in the 4.88 gears. Even before the Gears I saw only a very little change in Gas milage. Well see if there is a diffrence with the new gears (Engin not working so much to get to speed):purple: :purple: :purple: Good luck, must say 33" look good though


i was thinking that since i drive my jeep everyday and offroad only 1/4 of the time IF that, maybe i dont want 33 inch tires? and the type of offroad is different compared to most of u guys out there, here in saskatchewan, there isnt much for hills and rocks and trails, just the occasional mud pit in a field or something on the lines of that, maybe an odd rock or 2. do u think my gas milage will be pretty bad with 33s? its just a thought but i would like to know about the milage before i jump the gun and make a mistake that i will regret.
 
was there a big power difference when u changed up to 33 inchers? currently i am running 235s and they have about 1/5 of the tread (yea i know... they came with the jeep) and there is going to be alot of change in ride hieght stability, the amount of power etc. a buddy of mine suggested 31 inches tires, saying there would be more power getting to the ground, and i would be able to save some money (on lift, tires, etc.) if any of u guys out there have any ideas or suggestions it would help tons
 

If you are just driving it daily and hitting the local mudholes, consider a set of 31" mudders. I like the Interco Trxus MT's. They are an excellent all around tire good for both the street and the mud, and 31's won't hurt performance or mileage nearly as badly as a set of 33's. In addition, you can easly clear them with a 2.5" suspension lift ;)
 
thanks for the suggestion, i think i will go with the 31's, there is a sale at a local tire shop, $170 cdn for BFG MT depending on size and i have heard nothing but good things about the bfs. do u have any recommendations on a suspension lift, i am not looking to spend much money on the lift, just a regular lower end one thats not terrible but nothing specail, a 2.5 or 3 " lift is what i would be looking for. i will take out my 3" BDL and if i ever upgraded to 33's then i could just put it back in.
 
There was a bigger power difference and thus I changed the gears to 4.88 I love it now,,, I agree that if you don't want to regear, go with the 31"s

was there a big power difference when u changed up to 33 inchers? currently i am running 235s and they have about 1/5 of the tread (yea i know... they came with the jeep) and there is going to be alot of change in ride hieght stability, the amount of power etc. a buddy of mine suggested 31 inches tires, saying there would be more power getting to the ground, and i would be able to save some money (on lift, tires, etc.) if any of u guys out there have any ideas or suggestions it would help tons
 

thanks for the suggestion, i think i will go with the 31's, there is a sale at a local tire shop, $170 cdn for BFG MT depending on size and i have heard nothing but good things about the bfs. do u have any recommendations on a suspension lift, i am not looking to spend much money on the lift, just a regular lower end one thats not terrible but nothing specail, a 2.5 or 3 " lift is what i would be looking for. i will take out my 3" BDL and if i ever upgraded to 33's then i could just put it back in.
I have a Rubicon Express 2.5" Standard Duty on mine. It was on the Jeep when I bought it but I am real pleased with it. I would recommend it. It's a good value, probably the best quality you'll find at that price range.
 
i was looking at the RE and on the websites i seen its like 600$, i am looking for a 2.5 in suspension lift for around 400 or so, do u know of any companies that make one for that price range?
 
That's a tight budget for a suspension lift, especially since you will need shocks. There are some in that price range, you'll have to shop around.

This link has a bunch of kits, and I'm posting it just to give you an idea of the price range and maybe some brands to shop. I have no experience with this merchant, nor do I know if their prices are competitive. It's pretty much for reference but maybe they'll have your deal:
http://www.rockymountainsusp.com/jeep_YJ.htm

Check Jeepin outfitters, quadratec, 4wd hardware, Rusty's offroad, ebay... price shop them to death and get the best deal out there.

Good luck ;)

One thing to consider is this suspension will be under your Jeep for a long time. You may want to consider saving up a little more money and getting a better quality kit if you can wait. It would, in my opinion, be well worth it in the long run.
 

yea, that is a good idea, rather than spend the money again in replaced parts
 
Back
Top